HAMILTON Champion Casters offer superior performance and reliable service. A variety of wheel types to meet your needs. Features a 1" integrally-forged steel kingpin that is extremely durable and strong. -1/2" thick drop forged steel mounting plate with -3/8x3" plate steel legs are welded inside and outside to forged steel horn base. CNC-machined main load bearingA with 3-3/4" diameter raceway; 1" precision tapered thrust secondary load bearing counteracts radial thrust. Ball-check type lubrication fittings in swivel assembly and in wheel hubs with tapered or straight roller bearings.